Decay schemes for high-spin states inCl35,36,37andAr37from heavy-ion fusion-evaporation reactions

Abstract

The $\ensuremath{\gamma}$-ray decays of high-spin states in $^{35,36,37}\mathrm{Cl}$ and $^{37}\mathrm{Ar}$ were studied via heavy-ion-induced reactions involving $^{14}\mathrm{N}$ and $^{18}\mathrm{O}$ bombardment of targets of $^{24,26}\mathrm{Mg}$ and $^{27}\mathrm{Al}$. Decay schemes and spin-parity assignments were deduced from $\ensuremath{\gamma}\ensuremath{\gamma}$-coincidence measurements, $\ensuremath{\gamma}$-ray angular distribution and linear polarization measurements, and recoil-distance lifetime measurements. The observed levels are compared to predictions of the weak-coupling model. It is concluded that all the observed high-spin states can be assigned to configurations based on one- or two-nucleon excitations from the ($2s,1d$) shell into the ($1f,1p$) shell, and that not all the energetically available yrast levels of these configurations have, as yet, been found.NUCLEAR REACTIONS (HI, $\mathrm{xn}$, $\mathrm{yp}$, $z\ensuremath{\alpha}$) studies for $^{35,36,37}\mathrm{Cl}$ and $^{37}\mathrm{Ar}$, with $^{14}\mathrm{N}$, $^{18}\mathrm{O}$ projectiles, $^{24,26}\mathrm{Mg}$ and $^{27}\mathrm{Al}$ targets, $E=20\ensuremath{-}60$ MeV; measured $\ensuremath{\gamma}\ensuremath{\gamma}$ coin.; deduced levels; measured $\ensuremath{\sigma}({E}_{\ensuremath{\gamma}},\ensuremath{\theta})$ and ${P}_{\ensuremath{\gamma}}$; deduced ${J}^{\ensuremath{\pi}}$ for high-spin levels; measured recoil distance; deduced $\ensuremath{\tau}$. Natural and isotopically enriched targets, Ge(Li) detectors. Compared results to weak-coupling model predictions.